Diaphragm pump for a recirculating toilet

ABSTRACT

An improved pump filter for a recirculating toilet system includes a one-piece elastomeric diaphragm that is retained by a cover plate which is captured by a yieldable clamping ring. Normal pump operation is achieved through application of a pneumatic fluid such as compressed air. Potentially dangerous pressure excesses between the cover and the diaphragm can escape when the clamping ring holding forces are exceeded, and excess pressures tend to increase pressure to the &#39;&#39;&#39;&#39;O&#39;&#39;&#39;&#39; ring seal section thereby improving the liquid seal while relieving the excess or overpressure as the cover plate clamping ring yields in the preferred direction. A bead on the diaphragm periphery functions as an &#39;&#39;&#39;&#39;O&#39;&#39;&#39;&#39;-ring seal when the pump is mounted below the waste tank.

United States Patent 1 Molus 1 3,776,107 -Dec. 4, 1973 DIAPHRAGM PUMPFOR A RECIRCULATING TOILET [75] Inventor: Michael R. Molus, Chatsworth,

Calif.

[73] Assignee: Monogram Industries, Inc.,

Chatsworth, Calif.

Filed: July 3, 1972 Appl. No.: 268,928

3,634,891 1/1972 Kemper 4/10 Primary Examiner-Martin P. SchwadronAssistant ExaminerAbe Hershkovitz Attorney--William A. Kammel, Jr.

[5 7 ABSTRACT An improved pump filter for a recirculating toilet systernincludes a one-piece elastomeric diaphragm that is retained by a coverplate which is captured by a yieldable clamping ring. Normal pumpoperation is achieved through application of a pneumatic fluid such ascompressed air. Potentially dangerous pressure excesses between thecover and the diaphragm can escape when the clamping ring holding forcesare exceeded, and excess pressures tend to increase pressure to the Oring seal section thereby improving I the liquid seal while relievingthe excess or overpressure as the cover plate clamping ring yields inthe preferred direction. A bead on the diaphragm periphery functions asan O-ring seal when the pump is mounted below the waste tank.

4 Claims, 5 Drawing Figures PATENTEnnEc 4 m5 3776;107

SHEET 2 OF 2 Ha..// I A A1 3 xa DIAPHRAGM PUMP FOR A RECIRCULATINGTOILET The present invention relatesto a recirculating:sanitary system,and, more particularly, to-an improved pneumatic filter pump forproviding filteredflushing liquid, to a toilet.

In the patent to James M. Kemper, US. Pat; No. 3,567,032, issued Mar. 2,I971, and assigned to the assignee of the present invention, azfilterand pump fora recirculating sanitary system was shown which was adaptedto be placedzwholly within thestorage tank of the sanitary system andwas, in the preferred'embodiment, operated by a pneumatic system.Because the filter pump was intended to operate immersed in thestoragetank, the apparatus was enclosed in mating-members which weresealed ataperiphei'aI'flange; A diaphragm member was captured within.theflange and defined driving and driven portionsof the pump; Pneumatic fluid was applied to the driving-side of: the

pump and filtered flushing liquid wasstored and'applied to the toiletbowlfrom the drivensidei More recently, a patent issuedto James M.Kemper on Jan. 18, 1972, US. Pat. No. 3,634,89l1and assignedto theassignee of the present invention, which dis-' closed a similar concept.A first embodiment'includeda diaphragm pump driven by apneumaticsystemand an alternative configuration showed adiaphragma pump, whichwas mounted on the exterior. baseof; the

storage tank, andwhichwas driven by-a pedaLmember (of FIG. 18 of thepatent).

The present invention concerns animproved'filter pump which, in thepreferred embodiinentg, is also;

pneumatically operated and which is alsointended. to

be mounted to the outside'ofthe underside'of astoragetank in arecirculating sanitary system. According to the present invention, animprovedldiaphragm has beenable seal, which is held by a peripheral,resilient-clamp ing ring.

When the hydraulic pressure between the. plastic cover and the diaphragmexceedthe ambient pressure.

by a predetermined safe level, the holding ring has sufficientelasticity to permit an escape of'pneumatic fluid:- from between thediaphragm and the cover while still maintaining a fluid-tight sealbetween: the base' plate and the tank. Further, any leakage of flushingliquid from the pump would tend to be directed. into the tank since theperipheral bead of the diaphragm functions as A an o-ring seal.

An improved filter plateand comb conibinationis provided which is easilyinstalled and removed from the base plate using a plastic, interruptedflat-washer,

which retains the filter plate in a recess thatisprovided for. it.

The presentinvention is deemed to have'specific util-:

ity in vehicles which have a ready supply of pneumatic fluid available,such as busses-and trains. The device is- The novel features which arebelieved to be characteristic of the invention, both as to organizationand method of operation, together with further objects and advantagesthereof will be better understood from the following descriptionconsidered in connection with the accompanying drawings in which severalpreferred embodiments of the invention are illustrated by way ofexample. It is to be expressly understood, however, that the drawingsare for the purpose of illustration and de scription only and are notintended as'a definition of the limits of the invention.

FIG. 1 is a side view, partly in phantom-of a recirculating sanitarysystem incorporating an improved filter pump according to the presentinvention;

FIG. 2. is a top view, partly broken away of anim? proved filter pumpaccording to the present invention, taken-along line 22 of FIG. 1 in thedirection of the appended arrows;

FIG. 3is a side sectionalview of an improved filter pump ofFIG; 2takenalong theline 3-3 in the directionof the appended'arrows; 7

FIG. 4. is .an enlarged side sectional view of the mounting flange shownin FIG. 3 and identified as Section4-4; and

FIG. 5 is an enlarged sectional view of the retaining flange of FIG. 4yielding to relieve excess pneumatic pressurewithin the pump of thepresent invention.

Turning first to FIG. 1', there is shown a typical recircul'atingsanitary system '10, including a toilet 12, a tank 1'4, and a pump 16.The pump 16 operates in response to applied pneumatic fluidsuch ascompressed air in the preferred embodiment to pump filtered flushingliquid through the toilet. 12. On areturn stroke pump 16-fills withacharge-of. fluid that is filtered from the tank 14. As shown, thetoilet is provided with a decorative access coverfor a-drain valve 18and further includes alid' 20 and a seat 22.

Indicated in phantomview is a flush outlet line 24" .Pat. No.3,634,891.-

As shown in FIG. 2, the pump 16 includes a flushing fluid outlet port 28which connects to the flush line 24;

An-apertured filter plate 30 cooperates with a comb member having aplurality of pins 32', to permit flushing liquid topass fromthe tank 14totheinterior of the pump 16. As taught in the prior Kemper patents, thecombinationof the pins 32 and their associated apertures in plate 30,provides arestricted annular orifice which effectively prevents solid orparticulate matter from passing from the tank 14 to the pump 16. A splitwasher member 34 similar to a circlip seats in a circumferential groove36 to retain the filter plate 30 in place. A pump base plate 38 holdsthe filter plate '30 and fits into an opening provided in the tank 14. Aperipheral flange 40 fits snugly within an opening provided in thebottom 42 of the tank 14.

A diaphragm member 44:is made of ian elastomeric material and isprovided with a continuous peripheral head 46. The diaphragm 44 ismolded with a folded flange 48 at the periphery that encloses the'baseplate member 38, best seen in FIGS. 3-5,.described below.

In FIG. 3, the structural details-of the diaphragm pump 16 are shownmore clearly. On the outer surface termines the extent of diaphragm 44travel during the which bears against the diaphragm folded flange 48,

the edge of the base plate 38, and the exterior surface of the tankbottom 42. The inner surface of the cover flange 54 is provided with aseries of vestigial ribs 56 which help grip and hold the folded flange48. A peripheral ridge 58 cooperates with a flexible metallic holdingring 60 to maintain the cover 52 in a sealed relationship with theexterior of the tank 12, thus providing a fluid tight volume for drivingthe pump 16.

A heavy duty return spring 62 is provided to aid in the exhaust of thedriving fluid and to provide an intake stroke for the pump operationwhen the flushing action is completed. A rigid plastic spring supportmember 64 protects the diaphragm 44 from the return spring 62. Thereturn spring 62 and spring support member 64 urge the diaphragm 44 tothe full open position. A unidirectional intake flow valve 66 and aunidirectional outlet flow valve 68 enable the driven side of the pumpto fill during the intake stroke and to discharge the filtered flushingliquid into the flush outlet line 24 when driving fluid is applied tothe volume between the diaphragm 44 and the pump cover 52.

The filter pins 32 are formed as an integral part of a filter combassembly 70 which is mounted in a recess 72 that is provided in the baseplate 38. A stem element 74 includes a shoulder portion 76 which restsagainst an opening 78 in the filter recess 72. The stem 74 extends intothe driven chamber and contains a bias spring80 which holds the filterin a retracted position.

A reinforced strike plate 82 in the spring support member 64 moves thestem 74 and the comb assembly 76 when the driving fluid is applied tothe pump and the support member 64 is driven toward the base plate 38.The return spring 62 is positioned to surround the exterior of thefilter recess 72.

The diaphragm 44 includes a thickness ring 84 which spaces the diaphragm44 away from the inner wall of the pump cover 52. The thickened ring 84limits the travel of the bias spring 62. An'altemative configuration ofthe diaphragm 44 in the driving stroke is indicated in the dashed.outline. A driving fluid input line is provided but not shown.

The metallic holding ring 60 is fastened to a mounting ridge 86 with aplurality of screws 88 which, when secured, applies a compressive forceto the cover flange 54. The compressive force acts to create fluidtightseals on both the driving and driven sides of the pump.

In operation, pneumatic driving fluid under pressure is applied to thedriving side of the pump. As the pressure builds, the fluid applies aforce to the diaphragm 44 which overcomes the resistive force of thereturn spring 62. The diaphragm 44 moves upward, (as seen in FIG. 3)until the strike plate 82 engages the stem 74. As the volume in thedriven side decreases, filtered flushing fluid is forced out through,the valve 68.

At the end of the driving stroke, the stem 74 forces the filter combassembly and the pins 32 through the apertures in the filter plate 30.The fully compressed return spring 62 and the spring support member 64dedriving stroke.

Once the pressure of the driving penumatic fluid is released, the returnspring (62 urges the diaphragm downward (as viewed inF'lG. 3). The biasspring retracts the filter comb assembly 70 as fluid is drawn into thedriven side of the pump through the filter and the intake valve 66. Therate at which the pump fills with filtered liquid is determined by thereturn spring 62 and by the rate at which the pressure is relieved.

Turning next to FIG. 5, there is illustrated the manner in which thedifierential in pressure as betweenthe interior of the driving side ofthe pump and ambient in excess of what might be considered a safe levelis re-' lieved. The excess pressure in the interior is vented to ambientwhile maintaining a fluid tight seal of the tank and its contents byapplying a force against the metal holding ring 60. As shown, thepneumatic fluid escapes between the folded flange 48 of the diaphragm 44and the ribs 56 of the cover flange 54.

Thus there has been shown an improved, pneumatically operatedrecirculating toilet which includes a novel diaphragm member, that alsofunctions as a sealing gasket. Further, the diaphragm is provided with aperipheral bead which functions as an O-ring seal.

A molded cover bears against the diaphragm and defines the driving sideof the pump. The cover is held in place by a flexible retaining ring,which is prestressed to maintain a fluid-tight seal between the coverand the diaphragm. When excess pressure builds in the driving side ofthe pump, the retaining ring will, under such excess pressures, yield topermit the escape of pneumatic fluid between the cover and thediaphragm. The pneumatic fluid, acting upon the diaphragm, maintains afirm seal on the driven side of the pump and prevents the escape of anymaterial from the driven side.

Other modifications and embodiments will be obvious to those skilled inthe an and, accordingly, the scope of the invention should be limitedonly by the claims appended hereto.

What is claimed as new is:

1. A diaphragm pump including:

a. a diaphragm member having an enlarged neck portion adjacent theperiphery, said neck portion being adapted to receive a plate member;

b. a cover portion, including a flange adapted to seat against said neckportion and plate member, capturing a part of said neck portiontherebetween to produce a fluid-tight seal; and

c. a flexible retainer ring member mounted adjacent said cover portionand prestremed to apply a seating force on said flange, said coverportion and ring member responding to driving fluid pressures betweensaid cover portion and said diaphragm member that are greater by apredetermined amount than said seating force, to unseat said coverportion for relieving excess driving fluid pressures. v

2. The diaphragm pump of claim 1, above, wherein said diaphragm memberhas a bead at the peripheral edge thereof and said bead is adapted tofunction as an O-ring when said cover is seated.

3. The diaphragm pump of claim 1, above, wherein the surface of saidcover portion flange adapted to bear against said diaphragm memberincludes a plurality of ribs for improving the seal between said flangeand said diaphragm member.

4. For use in combination with a recirculating toilet create a drivingchamber between said cover memhaving a storage tank, a diaphragm pumpadapted to be her and said diaphragm member; and mounted in fluidcommunication with the Storage tank d. flexible retainer ring meansmounted to the storage comprising, in combination: tank, including aring member adapted to fitover a. a diaphragm member having a peripheraledge and 5 Said cover member flange, Said ring member being anelongated, fluid-receiving interior portion and an enlarged neck portionadjacent said peripheral edge;

b. a filterplate member adapted to be inserted into said enlarged neckportion to provide, in combina- 10 tion with said diaphragm member,upper and lower sealing surfaces, said filter plate member includingwhereby excesslve dflvmg u d pressure canovermeans for filtering thecontents of said storage tank come the force of Said ring member toPermit to id fl hi fl id; driving fluid leakage between said diaphragmc. a cover member having a peripheral flange 5 member and said covermember.

adapted to fit against one of said sealing surfaces to prestressed toapply a sealing force against said flange, said neck portion, saidfilter plate member, and the outer surface of the storage tank toprovide fluid-tight seals for retaining driving fluid and flushingfluid,

1. A diaphragm pump including: a. a diaphragm member having an enlargedneck portion adjacent the periphery, said neck portion being adapted toreceive a plate member; b. a cover portion, including a flange adaptedto seat against said neck portion and plate member, capturing a part ofsaid neck portion therebetween to produce a fluid-tight seal; and c. aflexible retainer ring member mounted adjacent said cover portion andprestressed to apply a seating force on said flange, said cover portionand ring member responding to driving fluid pressures between said coverportion and said diaphragm member that are greater by a predeterminedamount than said seating force, to unseat said cover portion forrelieving excess driving fluid pressures.
 2. The diaphragm pump of claim1, above, wherein said diaphragm member has a bead at the peripheraledge thereof and said bead is adapted to function as an O-ring when saidcover is seated.
 3. The diaphragm pump of claim 1, above, wherein thesurface of said cover portion flange adapted to bear against saiddiaphragm member includes a plurality of ribs for improving the sealbetween said flange and said diaphragm member.
 4. For use in combinationwith a recirculating toilet having a storage tank, a diaphragm pumpadapted to be mounted in fluid communication with the storage tankcomprising, in combination: a. a diaphragm member having a peripheraledge and an elongated, fluid-receiving interior portion and an enlargedneck portion adjacent said peripheral edge; b. a filter plate memberadapted to be inserted into said enlarged neck portion to provide, incombination with said diaphragm member, upper and lower sealingsurfaces, said filter plate member including means for filtering thecontents of said storage tank to provide flushing fluid; c. a covermember having a peripheral flange adapted to fit against one of saidsealing surfaces to create a driving chamber between said cover memberand said diaphragm member; and d. flexible retainer ring means mountedto the storage tank, including a ring member adapted to fit oVer saidcover member flange, said ring member being prestressed to apply asealing force against said flange, said neck portion, said filter platemember, and the outer surface of the storage tank to provide fluid-tightseals for retaining driving fluid and flushing fluid, whereby excessivedriving fluid pressure can overcome the force of said ring member topermit driving fluid leakage between said diaphragm member and saidcover member.